For centuries, the generation of electricity through steam has been a cornerstone of energy production, employing steam turbines to convert thermal energy into mechanical work effectively. This time-honored method remains prevalent today, with steam generated through various means, including the combustion of fossil fuels like coal or wood, harnessing the energy from nuclear fission, or utilizing stored thermal energy such as molten salt. However, the approach to steam generation has evolved significantly since the 19th century. Modern technologies, such as supercritical and pressurized systems, have dramatically increased the efficiency of these processes.

In a recent informative video, energy expert Ryan Inis delves into the innovative use of supercritical carbon dioxide (CO₂) as an alternative to traditional steam. The supercritical state of CO₂ is achieved when it surpasses a critical temperature of 31C and a pressure of 83.8 bar (or 8.38 MPa). This unique state presents numerous advantages when utilized in thermal power plants.

One of the most significant benefits of using supercritical CO₂ lies in its higher density, which allows for the design of smaller turbine blades. This reduction in size can contribute to the overall efficiency of power generation systems. Additionally, supercritical CO₂ has the potential for enhanced heat extraction capabilities, mirroring the advancements seen with the transition from boiling to pressurized water loops in both boiling water reactors (BWRs) and pressurized water reactors (PWRs). There are also emerging designs, such as gas-cooled and salt-cooled reactors, which can achieve even greater efficiency levels, exemplified by systems like the High-Temperature Reactor-Pebble Bed Module (HTR-PM) and Molten Salt Reactors (MSRs).

A 2019 article published in Power explored in-depth the various power cycles that utilize supercritical CO₂, including different Brayton cycles, some of which incorporate extra energy recovery mechanisms, and the Allam cycle, which is noted for its innovative approach to reducing emissions. However, the transition to this technology is not without its challenges. Corrosion remains a significant issue that engineers are actively addressing, and despite what has been posited in Iniss video, erosion also presents a concern when supercritical CO₂ is employed as a working fluid.

Nevertheless, many experts believe that the engineering challenges posed by supercritical CO₂ are not as daunting as those associated with supercritical steam generators, given that the critical point parameters for water are significantly more extreme. The ongoing research and development in this field could pave the way for transformative advancements in energy efficiency and sustainability in power generation, marking a promising era of innovation in the energy sector.